I notice that the two standards for garden hoses are 5/8 and 3/4 inch, or at least that's what I see the most of when I go to the store or online.

The thing I don't understand is I can't find an adapter to fit a 5/8 garden hose that I have to a 3/4 spout on the house. I see plenty of 3/4 to 1/2 inch which doesn't even make sense to me since I never see 1/2 garden hoses, and I can't find a 3/4 to 5/8 adapter anywhere at stores or online. Why?